add error for unsupported constant

examples/execve3.py

@@ -43,6 +43,7 @@ def hello_again(ctx: c_void_p) -> c_int64:
     key = 4
     last().update(key, ts)
     key = 5
+    st = "st"
     last().update(key, ts)
     return c_int64(0)
 

pythonbpf/functions_pass.py

@@ -53,6 +53,8 @@ def handle_assign(func, module, builder, stmt, map_sym_tab, local_sym_tab):
                           local_sym_tab[var_name])
             # local_sym_tab[var_name] = var
             print(f"Assigned constant {rval.value} to {var_name}")
+        else:
+            print("Unsupported constant type")
     elif isinstance(rval, ast.Call):
         if isinstance(rval.func, ast.Name):
             call_type = rval.func.id